Growing Cycle of Tulip Bulbs

The growing cycle of tulip bulbs continues year-round.

The life cycle of tulip bulbs (Tulipa) begins when you plant them in the fall. The best time for planting depends on your area’s U.S. Department of Agriculture plant hardiness zone. As a general rule, according to the National Gardening Association, plant tulip bulbs in September or early October in USDA zones 4 and 5, in October to early November in zones 6 and 7, in November to early December in zones 8 and 9, and late December to early January in zone 10.

Instructions for Zones 8 through 10

Chilling hours are essential to the tulip’s growth cycle and aren’t easy to come by in warmer areas and Mediterranean climates such as those in USDA hardiness zones 8 through 10. To overcome this obstacle, force the bulbs by placing them in the refrigerator inside a loosely closed paper bag for six to eight weeks before planting. Always keep them away from ripening fruit, which releases a gas that interferes with the tulip growth cycle.

In the Fall

For optimal growth, plant tulip bulbs 6 to 8 inches deep and space them at least two times the bulb’s width apart. In a warmer climate, take care to plant them 8 inches deep to keep them cooler longer. Once the bulbs are planted, the roots begin to grow.

In the Winter

In the cold of winter you might think tulips are in the dormant part of their growing cycle, but actually they never go truly dormant and continue to respond to the environment. During this time, the meristematic tissue of the roots, leaves and flowers develops. This type of tissue is the growth regulation center of the plant, and the presence of meristematic tissue means the bulb is healthy and ready to grow when temperatures get warm enough.

In the Spring

The tulip bulb’s growing cycle becomes more active in the spring and produces a small shoot as temperatures go up to about 60 degrees Fahrenheit. When temperatures reach about 68 F, the shoot grows into the plant and then flowers. At this time, the main bulb grows daughter bulbs, which become the main bulbs the following year.

In the Summer

Tulips have a short life cycle above ground, and these springtime plants begin to die in summer. Once the blossom matures and fades, it’s time to clip it off the plant -- but don’t’ clip the plant to the ground just yet. The green foliage provides the energy the bulb needs to grow the daughter bulbs to maturity. As the leaves yellow, the old bulb dies and you can now clip the plant to the ground.

About the Author

Victoria Weinblatt began writing articles in 2007, contributing to The Huffington Post and other websites. She is a certified yoga instructor, group fitness instructor and massage therapist. Weinblatt received her B.S. in natural resources from Michigan State University and an M.Ed. from Shenandoah University.